45 Degree Lean Back Alternate Knee Raise

Muscles worked

Setup

1. Sit on the floor with your knees bent and feet flat on the ground.
2. Lean your torso back to a 45-degree angle, maintaining a straight spine and proud chest.
3. Place your hands lightly on the floor behind your hips for balance, or cross them over your chest to increase the challenge.
4. Engage your core by pulling your belly button toward your spine to stabilize your lower back.

How to do it

1. Exhale as you lift one knee toward your chest, keeping the 45-degree torso angle perfectly still.
2. Inhale as you lower the foot back to the starting position with a slow, controlled tempo.
3. Immediately repeat the movement with the opposite leg, alternating sides for the duration of the set.
4. Focus on a 2-second lift and a 2-second lowering phase to maximize time under tension.

Form checklist

• Keep your chest lifted and avoid rounding your shoulders or lower back.
• Ensure your torso remains at a fixed 45-degree angle; do not rock back and forth as you move your legs.
• Keep your neck neutral by looking slightly upward rather than at your knees.
• Control the descent of the foot to prevent it from slamming into the floor.

Pro tips

• To maximize muscle engagement, imagine pulling your hip bone toward your ribcage as the knee rises.
• Pause for a split second at the top of the movement to emphasize the peak contraction in the lower abs and hip flexors.

Make it harder

• Extend your arms straight out in front of you to remove the support of your hands and increase core demand.
• Keep the non-working foot hovering an inch off the ground throughout the entire set to maintain constant tension.

Frequently asked

What muscles does the 45 degree lean back alternate knee raise work?

The 45 degree lean back alternate knee raise primarily targets the abs and obliques, and also works the glutes as secondary muscles.

What equipment do you need for the 45 degree lean back alternate knee raise?

The 45 degree lean back alternate knee raise requires no equipment — just your body weight.

Is the 45 degree lean back alternate knee raise good for beginners?

Yes. The 45 degree lean back alternate knee raise is a beginner-friendly movement and a strong foundation to build on.

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